: Hello. Like Dave from Minnesota, we in Iowa have received an unusual helping of snow, ice, and unrelenting sub-freezing temperatures this winter. Even my 4" vent stack has a nice, snowy dome covering it. I went so far as to climb the ladder to our rather steep roof before realizing that to proceed onto the icy surface was suicidal.

: I have 2 questions. First, since it appears that I'm stuck with the clog until we have an above-freezing day, is sewer gas a fire hazard? I know it's a potential health hazard from air-borne bacteria but the gas is venting from a basement floor drain located a few feet from our water heater and furnace.

: Second, would it help at all to put sheet metal vent covers on these PVC stacks, like the ones on our sheet metal furnace and water heater vent stacks? It doesn't help me now but it seems that this could help keep birds from nesting on the open stack and maybe cut down on the chance for snow clogs. I see a lot of open PVC vent stacks on surrounding homes, which makes me wonder if there is some reason for NOT installing some kind of vented cover.